The overheating of diesel engines is manifested by excessively high cooling water temperature, which exceeds the normal range of 80℃ - 90℃, and even reaches 100℃. Overheating can cause deformation of various parts of the engine, decrease the viscosity of the engine oil, accelerate part wear, and also cause premature combustion of the mixture and reduce the power of the diesel engine due to overheating. The causes of overheating include:
The cooling system is not working properly. Mainly: insufficient circulating water cooling.
(1) The fan belt is loose, or the fan blades are installed in the wrong position.
(2) The air duct of the radiator is blocked.
(3) The cross-section of the water pump impeller is worn, and the pump's water delivery capacity decreases.
(4) There is too much scale in the water jacket and radiator or the water pipes are blocked.
① The diesel engine works under overload for a long time.
② The fuel injection timing is too early, the engine body temperature is high, the exhaust emits black smoke, and the operation is weak. The fuel injection timing needs to be adjusted.
③ There is too much carbon deposits on the piston, piston rings, and cylinder head. The carbon deposits should be removed.
④ The clearance of the exhaust valve is too large. This causes the opening time of the exhaust valve to be shortened, and the exhaust gas in the cylinder cannot be discharged in time, resulting in overheating of the machine and a decrease in the power of the diesel engine. The valve clearance should be adjusted according to regulations.